Need to get a shift govern kit. The govern is in under the 3" round dome looking thing on the side of the transmission. The cover just pry's off and you can pull out the governor. The govern has weights on it (like a distributor advance) and the heavier the weights the sooner it shifts. There are some welded weights on the spinner that you can cut off. The lighter the weights, the later it shifts. There is a govern kit available that has different weights and springs.